In-plane switching mode liquid crystal display (IPS-LCD) panels are becoming more and more popular because they can present a wider viewing angle to a viewer than twisted nematic (TN) mode LCD panels. Generally, an IPS-LCD panel includes two opposite substrates and a liquid crystal layer coupled between the two opposite substrates. Liquid crystal molecules in the liquid crystal layer are arranged along a predetermined orientation by an alignment layer in an initial state. When a voltage is applied to form an electric field within the liquid crystal layer, the liquid crystal molecules are twisted to realize a display function of the IPS-LCD.